Famous Face Dolls Company manufactures and sells custom dolls through a network of specialty stores. The face of each doll is hand-painted by a highly skilled craftsperson in the image of a popular public figure. Large dolls (7580cm) sell for $200 each and have a unit variable cost of $90. Each large doll requires 30 minutes of painting time. Small dolls (4045cm) sell for $100 and have a unit variable cost of $65.00. Each small doll requires 15 minutes of painting time. TYpical demand is 150 large dolls and 500 small dolls per month. Due to upcoming vacations, the amount of available face-painting time is limited to 180 hours for the next month. The contribution margin per hour of painting time is: a. $1.67/ hour for large dolls and $7.69 /hour for small dolls b. $290/ hour for large dolls and $165/ hour for small dolls c. $220 /hour for large dolls and $140/ hour for small dolls d. $110/ hour for large dolls and $35/ hour for small dolls